A great book on life in a modern city is this, CITY: REDISCOVERING THE CENTER by William H. Whyte.
It’s also one of my favourites. Whyte, famous for an earlier book, The Organizational Man, had been part of a group that:
‘… studied the use of urban spaces for 16 years. This follow-up to The Social Life of Small Urban Spaces is an engaging look at the variety of human interactions which make “downtown” vibrant. Whyte looks at such diverse topics as pedestrian movement, concourses and skyways, sunlight and its effects–all from the perspective of a confirmed city-lover. His observations and recommendations can be read with profit and pleasure by professional planners and readers interested in what makes a city tick.’
I actually saw this book in action in Toronto. On Bloor Street near St. George Street was a small park that was semi-secluded behind of a series of low walls. Even though it was in a vibrant part of the city, no one ventured in there, likely because of it’s closed nature and the down-and-out men who occupied it (and who seemed to be fighting more often than not). After reading this book, I thought, if they tore down those walls, the space would open up and you would get more people using the space. (No public space should be dominated or controlled by one group, rich or poor, I believe.) Eventually the walls were torn down and that is what happened: the space was used by a much more diverse group of people and it was more peaceful.
Since that time more and more people have been rediscovering the city centre, in part due to the work of people like Whyte and Jane Jacobs. Anyone who would love to live in a city or who already does would get a much greater appreciation of urban life if they read this book.
Smart People I Know 
I saw the nucleus of this book on a television program in about 1981, and it changed my whole perspective about urban planning and social behavior. I enjoyed the program and the book very much, but find it a bit out of date now – people use spaces differently now, and the late-80s analysis of market forces and trends in planning and business siting need to be updated. I wonder what Whyte would say about the number of people now excluding themselves from the mileu by using headphones or keeping their heads down while texting/etc?
I think Whyte would be fascinated by how people interact differently with the city now, especially with things like ipods and cell phones. It would give him whole new areas to work on! And he would love augmented reality! I also think he would like the return to the city happening more and more.